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                       TRANSPORTATION DIVISION

                                                            STAFF REPORT

                             

TO:             PLANNING & TRANSPORTATION COMMISSION

FROM:                       Carl Stoffel                                            DEPARTMENT:     Planning and

                                                                                                                 Community Environment

AGENDA DATE:      February 25, 2004

SUBJECT:                 Downtown North Traffic Calming Project--Recommendations to Remove Current Trial Plan and Implement New Traffic Calming Plan

RECOMMENDATIONS

Staff recommends that Planning and Transportation Commission (PTC) recommend that the City Council take the following actions.

•  End the current Downtown North trial traffic calming plan;

•  Adopt the attached resolution (a) approving a mitigated negative declaration for permanent implementation of the Downtown North Traffic Calming Project Mixed Measures Plan (or other plan with similar or less impacts), (b) approving permanent implementation of the Mixed Measures Plan including performance measures and improvement actions, and (c) authorizing the Director of Planning to implement improvement actions as necessary to achieve the Plan's performance measures.

BACKGROUND

The PTC opened the discussion of this project at its January 21, 2004 meeting. A public hearing was concluded after taking testimony from approximately 90 citizens. The PTC approved a motion to recommend to Council that the resident opinion survey for the current trail plan not be conducted. The PTC did not take action on staff's recommendations, but requested additional related information, and adjourned to a walking tour meeting of the neighborhood for January 24, 2004, which was appropriately noticed in City Hall. No public testimony was taken at that meeting. This staff report presents a substantial amount of new information, as follows:

1.    A revised environmental assessment with mitigated negative declaration for the Mixed Measures Plan or other plan with similar or less CEQA (California Environmental Quality Act) impacts;

2.    Performance measures and improvement actions for the Mixed Measures Plan

3.    Answers to Commission questions and requests for additional information;

4.    Summary of the January 24 walking tour; and

5.    Some responses to public testimony.

In this report, extensive references are made to the January 21, 2004 staff report to the PTC on the Downtown North project (attached). At the Commissioners' request, two additional staff reports are included (in the Commissioner's packets only) covering the original discussion and approval of the trial plan: October 11, 2000 report to the PTC and the December 11, 2000 CMR:440:00.

Staff's recommended Mixed Measures Plan is illustrated below and was described in the 1/21/04 staff report. The Mixed Measures Plan is expected to solve or reduce most of the problems with the current trial plan while still maintaining some through traffic reduction, albeit substantially less than attained by the current trial plan. The plan consists of removing three of the seven street closures of the current trial plan and relocating one of the remaining four; removing the two gateway features near Middlefield; keeping the Waverley bulbout; adding three traffic circles on Everett and Hawthorne and a speed table to the existing gateway on Everett at High; and implementing peak hour turn restrictions into the neighborhood from Alma and Middlefield. The intersection improvements at Lytton/Middlefield and Lytton/Alma will remain as permanent improvements to the arterial roadway system.



DISCUSSION OF IMPORTANT ISSUES AND ADDITIONAL INFORMATION

Performance Measures and Improvement Actions

Performance measures for the Mixed Measures Plan are based on those originally established for the current trial plan, but with modifications to conform to the new recommended plan. Staff expects that the Mixed Measures Plan would meet all the performance measures and would therefore not require and adjustments. Nevertheless, staff recommends that the Director of Planning be authorized to implement “improvement actions” to address any possible failure of the plan to reach any performance measure(s). Together, the performance measures and improvement actions would insure that the Mixed Measures Plan (or plan with similar impacts) could be implemented permanently with all performance measures being met.

Monitoring and implementation of the improvement actions, if required, would proceed as follows. Four months after permanent implementation of the Mixed Measures Plan (or plan with similar impacts), staff would begin measurements to verify that the new plan meets the performance standards, with certification by the Director of Planning and Community Environment. This certification would occur approximately five months after implementation of the plan. If a performance measure is not being met, the Transportation Division would select the appropriate improvement action(s) from the list of actions already approved by the PTC and Council (see list below), and recommend that the Director of Planning and Community Environment approve implementation of the action(s). The revised plan would then be monitored for another four months to make sure that the performance measures are met, following the same methodology as the first round of monitoring and verification. If necessary, additional improvement actions on the list could be implemented.

Following is a list of the performance measures and associated improvement actions for the Mixed Measures Plan. Five of the performance measures are intended to also serve as mitigation measures addressing traffic diversion, intersection level of service, and fire and police response times (CEQA mitigations). These are further discussed in the Mitigated Negative Declaration (included under separate cover). All the performance measures are project goals and their implementation with the improvement actions will insure that these goals are met in an efficient manner. Some of the performance measures do not have quantitative standards, so are subject to some interpretation or are intended to provide information. The CEQA performance measures take precedence over the non-CEQA performance measures, and their implementation might result in non-CEQA performance measures not being reached—most likely performance measure #1. Staff recommends that the PTC recommend that Council approve the following list of performance measures and improvement actions as an integral part of permanent implementation of the Mixed Measures Plan.

Through Traffic Reduction (project goal; Non-CEQA Measure)

•  Through traffic will be reduced by an average of at least 35 percent compared to the February 2003 “before trial” condition. The Downtown North neighborhood cordon count of average daily traffic (sum of daily counts at all neighborhood access streets along Middlefield, Lytton and Alma) will be the basis for this calculation.

Improvement actions for performance measure 1:

1a.     Increase hours of weekday turn restrictions into the neighborhood to 7 AM – 6 PM on either or both Alma and Middlefield, as recommended by Transportation Division to meet goal. (This action reduces the amount of through traffic entering the neighborhood, and can be fine-tuned.)

1b.     Implement Modified Mixed Measures Plan (refer to Attachment B) (This action increases the difficulty to traverse the neighborhood, thus causing more through trips to stay out of the neighborhood.)

Diversion of Traffic to Other Streets (CEQA Mitigation)

•  On local and collector streets with “before” counts of less than 2500 vehicles per day (vpd) in the Downtown North and Lytton neighborhoods, no average daily vehicle count at a peripheral or internal location will increase by more than 25 percent of the “before” count. On local streets, the addition will not cause the volume to exceed 2500 vpd ­ + 10 percent.

Improvement actions for performance measure 2:

2a.     Install the following additional traffic calming measures to the Mixed Measures Plan on street segments or at ends of street segments where diversion standard is exceeded, as recommended by Transportation Division to meet standard: one speed hump per block and/or traffic circle at intersections where stop signs are not present. (This action increases the travel time and adds inconvenience to street the problem street segments, thus slightly decreasing through trips.)

2b.     Implement Modified Mixed Measures Plan (This action increases the difficulty to traverse the neighborhood, thus causing more through trips to stay out of the neighborhood and reducing through trips on the problem segments.)

2c.     Implement No Closure Plan (refer to Attachment B) (This action removes all street closures, so traffic diversion in specific blocks is greatly reduced.)

•  On local streets with a “before” count of 2500 vpd or greater in the Downtown North and Lytton neighborhoods, no average daily traffic count at a peripheral or internal location will increase by more than 10 percent of the “before” count.

Improvement actions for performance measure 3:

Same as items 2a, 2b, and 2c listed above.

•  The AM or PM peak hour level of service (LOS) at the Lytton/Alma and Lytton/Middlefield intersections will not degrade to less than LOS D.

Improvement actions for performance measure 4:

4a.     Change signal phasing and/or timing. (This action is can be used to fine tune the allotment of green time, thus increasing signal efficiency and improving LOS.)

4b.     Reduce, change or remove totally weekday peak hour turn restriction hours as recommended by Transportation Division to meet standard. (This action can be used to incrementally reduce the forced use of the arterial streets during peak hours, thus decreasing volumes passing through the intersections and improving LOS.)

Speed Reduction (Non-CEQA Measure)

•  This is not a performance measure for the Mixed Measures Plan. If the PTC or Council wished to establish this (or something similar) as a performance measure, the following associated improvement action is identified:

Install the following additional traffic calming measures to the Mixed Measures Plan on street segments or at ends of street segments where speed reduction goal is not reached, as recommended by Transportation Division to meet goal: one speed hump per block and/or traffic circle at intersections where stop signs are not present. (This action reduces speeds in the specific blocks.)

Crashes (Non-CEQA Measure)

It is usually not possible to identify a statistically significant pattern of crashes on local streets in a four-month period, due to low traffic volumes. Crash trends on low volume streets are usually only discernable after several years.

•  There will be no identifiable crashes directly attributable to the traffic calming plan elements in the Downtown North neighborhood. If sufficient data is available, the crash rate in the neighborhood and on the three surrounding arterials should be compared to that before the measures were installed.

Improvement action for performance measure 6:

6a.     Implement No Closure Plan. (This action assumes that the street closures in the Mixed Measures Plan would be the primary cause of crashes, and would totally change the traffic calming elements to remove them.)

•  At the Middlefield/Everett intersection, there will be no more than 3 crashes caused by a vehicle entering or leaving Middlefield via either leg of Everett. [Since 1995, an average of approximately six such accidents per year have occurred at this location.]

Improvement action for performance measure 7:

7a.     Install right turn only restrictions on Hawthorne and Everett at Middlefield for time periods as indicated by crash analysis. (This action can be used to fine-tune the reduction of outbound left turns and through movements, which are the primary crash-prone movements. Hawthorne must be included to keep drivers from moving from Everett to Hawthorne.)

Fire and Police Responses (CEQA Mitigation)

8.       The travel times for Fire and Police Department calls within and near the Downtown North neighborhood will not exceed the Departments' mission goals for travel time of 4 minutes for 90 percent of fire and basic medical responses, 6 minutes for 90 percent of advanced medical responses (paramedics), and 3 minutes for police calls—attributable to implementation of the traffic calming plan.

Improvement actions for performance measure 8:

8a.     Install flexible, break-away or automatic retractable bollards at one or more closure locations deemed to be problem(s) by the Fire or Police Department. (This action allows Fire Department vehicles to traverse the closures with only minimal delay.)

8b.     Implement No Closure Plan (This action removes all street closures as traffic calming elements.)

9.       There will be no serious impediments in any emergency activities, including identifiable trends in increases in travel times during the trial period, of the Fire and Police Departments within and near the Downtown North neighborhood attributable to the traffic calming plan. This includes Fire Department access to Lytton Gardens and Webster House.

Improvement actions for performance measure 9:

Same as items 8a and 8b above.

Citizens' Observations and Incident Reports to Police Department (Non-CEQA Measure)

10.     Citizens' reports of safety problems within and near the Downtown North neighborhood attributable to the traffic calming plan will be compiled. Any reports or calls for service to the Police Department (other than crashes reported above) will be evaluated. This measure does not have a specific performance goal.

Neighborhood Acceptance (Non-CEQA Measure)

11.     A neighborhood opinion survey will not be conducted for the Mixed Measures Plan.

Other Issues (Non-CEQA Measure)

12.     Impacts attributable to the traffic calming plan as reported by City departments, PASCO, the Post Office, transit operators, and any other public agencies serving the neighborhood (including bordering arterials) will be compiled and evaluated. This measure does not have a specific performance goal.

Answers to Commission Questions and Requests

Commissioners requested additional information about this project at the 1/21/04 PTC meeting and the 1/24/04 walking tour. The questions are listed below, with answers in Attachment C.

•  Provide another alternative plan that uses aggressive traffic calming measures, not including street closures, that is not cost-constrained.

•  Compare the traffic volume measurements from 2000 when the current trial plan was originally proposed to the measurements from 2003 just before the plan was actually implemented. Discuss the change in volumes in that three-year period. There were some anomalies. Some areas where we thought there were going to be reductions there actually were increases.

•  Comment on the pedestrian benefits of bulbouts and if we can consider installing bulbouts at all four corners of Johnson Park.

•  Where did the diverted vehicles go?

•  Comment on Unblock's report on issues related to the California Vehicle Code (CVC) and the California Environmental Quality Act (CEQA).

•  How do levels of through traffic in Downtown North (before the trial) compare to University South or other neighborhoods?

•  How can the volume increases caused by the current trial plan on both sides of Johnson Park be improved (i.e, on Kipling and Waverley)?

•  Explain how each plan affects the problem of diverted volumes within the neighborhood.

•  What are the possibilities to alleviate the condition by Stanford Electric?

January 24, 2004 Walking Tour

Commissioners requested a meeting in the Downtown North neighborhood to see certain aspects of the plan up close, with staff present to provide comment and answer questions. The number of members of the public varied from about two to six. No public testimony was taken. Five Commissioners were present, with four staff members. The walking tour focused on locations in the neighborhood where the plan has been most effective and where the most problems were encountered. The meeting was held on a Saturday morning, so observing actual weekday traffic flows was not possible nor was an objective of the tour. Much of the information presented and discussed was in the January 21, 2004 staff report. Some additional information is included in answers to Commissioners' questions in Attachment D.

Further Information on Policy Issues Raised in Public Testimony

Policies for Closure of Streets to Through Traffic

This issue has been discussed extensively in prior reports for the Downtown North project:

            10/11/00 staff report to PTC, pp 4-7

            12/11/00 CMR:440:00, pp 3-8

            1/21/04 staff report to PTC, pp 9-10

CVC 21101(f) allows cities to use traffic barriers (aka street closures) and other design features to implement the circulation element of the general plan. The Palo Alto Comprehensive Plan, adopted by Council resolution, contains criteria for street closures to through traffic in Policy T-33 (“overwhelming through traffic” and “no acceptable alternatives”). The Transportation element contains other goals and policies that promote traffic calming. The requirements of Policy T-33 are not quantitative and thus require interpretation. Transportation Division provided the interpretation of that policy: (a) “Overwhelming through traffic” is 60 percent or more. (b) Based on the Dowling Associates study in 1999, the neighborhood residents' statements at the various neighborhood meetings and surveys in 1999-2000, and staff's knowledge of other neighborhood projects, staff concluded that “acceptable through traffic reduction for this project could only be attained by street closures”. To come close to significant through traffic reduction with other non-closure measures, such as circles and humps, would have meant installation of an unacceptably large number of measures, both in terms of cost and neighborhood acceptance. The City Council based its finding and determination on the traffic counts taken in mid-1999 (which documented that some streets in the Downtown North neighborhood experienced through traffic at a level exceeding 60 percent) and the Traffic Division's judgment that those conditions will continue and worsen in the future. The fact that the intervening traffic counts (February 2003) showed a lesser percentage of through traffic represents only a temporary departure from the trend of increased through-traffic on these streets (further information about these counts is contained in the answers to one of the Commissioners' questions).

Use of Street Closures in Staff-Recommended Mixed Measures Plan. On pp 7+ of the 1/21/04 staff report, staff identified several other plans to correct deficiencies of the current trial plan. Staff explained on pages 7 and 8 that it does not have the staffing and funding to develop and manage a trial and evaluation of a completely new aggressive, non-closure plan to meet the project goals (see Guidelines on page 1 of Attachment D to the 1/21/04 report). Instead, staff has proposed plans that tier off the current plan to varying degrees, most of which still include street closures for the same reason as the current trial plan. Staff's recommendation—the Mixed Measures Plan—is the only plan that staff is reasonably confident could successfully eliminate or reduce the problems with the current trial plan, yet still meet the original project goals as much as possible.

Length of Trial. In all past and current neighborhood and spot treatment traffic calming projects, a four to six month trial has been employed. The evaluation period usually begins before the trial is over, and almost always extends significantly beyond the trial period. For the Downtown North project, staff began the collection of evaluation data unusually early—just three months into the trial period—to respond to the intense controversy of the project. In many past projects, changes to the trial have been proposed and designed while the trial elements remain in place awaiting the changes. In many cases, significant delays occur due to heavy staff workload as well as heavy demands for PTC and Council agendas. Staff does not attempt to define a trial period to include the full potential time period that a trial plan will be in place, including all foreseeable delays and extra time needed in case a trial plan needs to be modified. The length of the trial periods are viewed as guidelines and not as binding deadlines as long as the evaluation task is proceeding as expeditiously as possible.

ENVIRONMENTAL REVIEW

A mitigated negative declaration (MND) was prepared for proposed traffic calming project and released on February 24, 2004.   The MND is circulating for 20-day comment period ending on Monday, March 15, 2004. The MND was provided to Commissioners under separate cover and is available to the public in the Transportation Division office and public libraries.

The PTC received a previous draft of the Initial Study with the January 2004 staff report.   The Initial Study has been modified to incorporate the staff's recommended Mixed Measures Plan, and other plans or variations that have approximately similar, or less, potential environmental impacts than the proposed plan, as described elsewhere in this staff report.   This provides the PTC with more flexibility in its recommendations for the Downtown North Traffic Calming project.

The MND includes mitigation measures to reduce potential environmental impacts of the Mixed Measures Plan and variations to a less than significant level in the areas of traffic, public services, air quality, cultural resources & noise.   Mitigation measures in the form of performance standards are incorporated into the project and monitoring of the proposed project will occur for 4 months following installation.   In the event that the performance standards are being exceeded, the Director of Planning will take steps based on recommendations of the Transportation Division to modify the traffic calming measures (as described above) so that the standards are met.  

PUBLIC NOTICE

Notification was mailed on February 10, 2004 to each household, business and non-resident owner of property in the area described in Attachment B of the 1/21/04 staff report. The mitigated negative declaration was noticed as described in the preceding paragraph.


ATTACHMENTS/EXHIBITS :

A.      Resolution

B.      Modified Mixed Measures Plan and No Closure Plan

C.      Commissioners Questions and Staff Reponses

•  January 21, 2004 Commission Report Downtown North-- Recommendations to Remove Current Trial Plan and Implement New Traffic Calming Plan

•  January 21, 2004 Commission Meeting Minutes

The two reports listed below are being provided only to the Commission Members

•  CMR:440:00, 12/11/00, Downtown North Neighborhood Traffic Calming Study

•  October 11, 2000 Commission Report, Downtown North Neighborhood Traffic Calming Study

COURTESY COPIES :

DTNNA representatives (Dan Lorimer, Chas Pavlovic, Mike Liveright, Josh Mogal)

Unblock representatives (Joe Durand, Dana DeNault, Pat Markevitch)

Lytton neighborhood representatives (Alan and Bonnie Luntz)

Palo Bicycle Advisory Committee Members

City of Menlo Park Transportation Division

Prepared by:       Carl Stoffel, Transportation Engineer

Reviewed by:       Joseph Kott, Chief Transportation Official

Division Head Approval:                                                                                          

Joseph Kott, Chief Transportation Official


ATTACHMENT A

[INSERT RESOLUTION]



ATTACHMENT B

MODIFIED MIXED MEASURES PLAN

Staff developed this plan after public comment was received at the January 21, 2004 Commission meeting. It is included in the performance measures for the Mixed Measures Plan as an “improvement action”. The purpose of this plan is to solve or reduce most of the problems with the current trial plan while still maintaining substantial through traffic reduction. The plan consists of removing two of the seven street closures and relocating one of the remaining four; removing the two gateway features near Middlefield; keeping the Waverley bulbout and both arterial intersection modifications; adding two traffic circles on Everett and Hawthorne and a speed table to the existing gateway on Everett at High; and implementing peak hour turn restrictions into the neighborhood from Alma and Middlefield. Approximate cost to remove some trial measures, install new measures, and gather new traffic counts: $76,000

Advantages

•  Provides substantial volume reduction with a combination of measures, including five street closures--about 65 percent through traffic reduction (reduction of about 3600 daily through trips or 7200 daily entries/exits) compared to about 90 percent with current trial plan (reduction of about 5000 daily through trips or 10,000 daily entries/exits)

•  Maintains protection for Palo Alto Avenue

•  Speed reduction to 15 mph at one location each on Hawthorne, Everett and Webster

•  Less traffic diversion within the neighborhood than with current trial plan, not expected to exceed the 25 percent maximum increase threshold on most local streets (see disadvantages below). Less driver confusion and unexpected behavior

•  Slightly fewer impediments to Fire Department vehicles and other services than current trial plan (two fewer street closures, including removal of one next to Fire Station 1). Circles are acceptable to Fire Department

•  Less congestion on a daily basis on arterials and at Alma/Lytton and Middlefield/ Lytton than with current trial plan

•  Closure next to Stanford Electric removed

•  Two gateways near Middlefield removed

•  Maintains crash reduction potential at Middlefield/Everett


Disadvantages

•  Traffic diversion on some low-volume segments on north side of neighborhood (such as Cowper, Ruthven and Tasso) might still exceed the 25 percent maximum increase threshold—verification required

•  Despite improvements, most impediments to Fire Department vehicles and other services still remain

•  Weekday peak hour turn restrictions cause moderate increase of peak hour traffic and queuing on arterials and at Alma/Lytton and Middlefield/Lytton intersections, but LOS remains acceptable

•  Palo Alto Avenue traffic at Middlefield added to traffic on Hawthorne and Everett (as with current trial plan)

•  Inbound weekday peak hour turn restrictions will force residents to use Lytton and north-south neighborhood streets for access to/from neighborhood during those hours

•  Weekday peak hour turn restrictions require Police Department occasional enforcement, competing with other peak hour traffic enforcement needs. Expected violation rate of approximately 20 percent would generate some complaints to the City, with little to no additional enforcement response possible.

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NO CLOSURES PLAN

This plan was originally presented in Attachment D of the January 21, 2004 staff report. It is now included in the performance measures for the Mixed Measures Plan as an “improvement action”.   The purpose of this plan is to provide an option without any totally closed streets that provides a minimal degree of through traffic reduction. The plan consists of removing all the street closures and the two gateway features near Middlefield; retaining the bulbout on Waverley and both arterial intersection modifications; adding three traffic circles on Everett and Hawthorne and a speed table to the existing gateway on Everett at High; and implementing peak hour turn restrictions into the neighborhood from Alma and Middlefield. This option keeps streets mostly open and offers a minimal level of through traffic reduction by means of the combinations of measures. The circles and speed table also help reduce speeds in their vicinities. Traffic circles permit all intersection movements and would be similar in concept to the one on Lytton at Fulton. An example of a speed table is located on Channing at Lincoln. Approximate cost to remove most trial measures, install new measures, and gather new traffic counts: $94,000

Advantages

•  Returns streets to mostly “open” status with substantially reduced detours, driver confusion or unexpected behavior

•  Speed reduction to 15 mph at 4 locations on Hawthorne and Everett

•  Substantially less traffic diversion problems than with current trial plan—mostly during weekday peak hours. Cases of exceeding 25 percent maximum increase threshold on any given local neighborhood street not expected but should be verified through a trial

•  No impediments to emergency access and minimal for other services. Circles are acceptable to Fire Department

•  Less congestion on arterials and at Alma/Lytton and Middlefield/Lytton on a daily basis than with current trial plan

•  Less maintenance required than with current trial plan

Disadvantages

•  Minimal volume reduction from combination of measures--about 20 percent through traffic reduction (reduction of about 1100 daily through trips or 2200 daily entries/exits) compared to 90 percent with current trial plan (reduction of about 5000 daily through trips or 10,000 daily entries/exits). Consequent decrease of advantages resulting from less traffic on neighborhood streets, as originally desired by neighborhood representatives and as embodied in City Council approval to implement the plan

•  Weekday peak hour turn restrictions cause moderate increase of peak hour traffic and queuing on arterials and at Alma/Lytton and Middlefield/Lytton intersections, but LOS remains acceptable

•  Inbound weekday peak hour turn restrictions will force residents to use Lytton and north-south neighborhood streets for access to/from neighborhood and somewhat restrict access for non-emergency services during those hours

•  Accident reduction potential at Middlefield/Everett less than current trial plan

•  Weekday peak hour turn restrictions require Police Department occasional enforcement, competing with other peak hour traffic enforcement needs. Expected violation rate of approximately 20 percent would generate some complaints to the City, with little to no additional enforcement response possible.

•  Most expensive to implement





ATTACHMENT C

COMMISIONERS QUESTIONS AND STAFF RESPONSES

Questions and requests from Commissioner Burt.

•  Provide another alternative plan that uses aggressive traffic calming measures, not including street closures, that is not cost-constrained.

The Downtown North neighborhood includes approximately 17 interior streets, 3 external streets, with 63 internal blocks and 18 external blocks, and 45 intersections. Several types of traffic calming measures could be considered for each of the blocks and intersections, including speed humps, speed tables, traffic circles, turn restrictions, medians, and bulbouts. Thus, there are literally hundreds of traffic calming plans and permutations that could be considered for Downtown North. Several non-closure plans were presented to residents in the 1999-2000 planning process for this project. These were included and discussed in the October 11, 2000 staff report to the Commission and the December 11, 2000 CMR:440:00 (both attached for Commissioners). Two of these alternatives most favored by residents at that time were discussed in Attachment B of CMR:440:00 and compared to the current trial plan that is now in place. In response to Commissioner Burt's request, the most aggressive of these two plan (Plan 03) is illustrated below. It consists of 22 traffic calming measures, including 14 traffic circles. The approximate cost to implement this plan using low-budget designs similar to the current trial plan elements is approximately $255,000 (not including about $30,000 to remove the existing trial street closures). During the planning process in 1999, that cost was approximately 3 –4 times higher because cost estimates for the permanent installation were based on high-quality landscaped and irrigated circles, which the City does not now fund. Both staff and residents did not consider this plan as acceptable because its cost was much higher than the current trial plan that was ultimately recommended, with only 11 traffic calming measures.

Another possible aggressive non-closure plan would be a plan with a speed hump or table in every major block, instead of a traffic circle at each intersection. An example of such a plan would have 34 speed humps or tables on nearly every street in the neighborhood (not illustrated). The cost of such a plan using speed humps would be about $170,000. If speed tables were used, which cost about twice as much as speed humps, the cost would be about $375,000. Neither estimate includes about $30,000 to remove the existing trial street closures. During the neighborhood meetings held during the planning process in 1999, residents attending the meetings strongly disapproved of speed humps as an alternative. The primary reasons given were the large number that would be needed, the impact on emergency response, and the aesthetic impact of the measures. Cost was not the issue with speed humps. Staff therefore did not offer this type of plan as an alternative for Downtown North.



2.          Compare the traffic volume measurements from 2000 when the current trial plan was originally proposed to the measurements from 2003 just before the plan was actually implemented. Discuss the change in volumes in that three-year period. There were some anomalies. Some areas where we thought there were going to be reductions there actually were increases.

Anomolies, variations, error range . All traffic counts for this project were taken with hose counters for a minimum of 48 hours of data taken on two midweek days, then averaged to a single 24 hour count representing a typical midweek day, expressed as vehicles per day (vpd). Traffic volume measurements can easily vary by + 10 percent on any given day, with additional seasonal variations. Schools being open and closed, including Stanford University, also affect counts seasonally. (Note: even when Stanford is not in normal session during the summer, many functions continue summer-long, including staff functions, some graduate students, undergraduate summer school and many special activities.) Measuring counts for 48 hours instead of just 24 hours improves accuracy somewhat, but does not overcome the random daily or seasonal variations. Roadway conditions, including unknown construction activities outside the area, can also affect travel patterns and volume counts at any time. Further substantial differences in counts can result from “measurement errors”. For example, the May 1999, February 2003, and September 2003 counts were all made by different data collection contractors using different types of equipment. In some cases, a counter can be placed before or after a major driveway in the same block, resulting in some major count differences just due to an improper location, despite engineers' best efforts at quality control. This would be especially true in the north-south blocks next to Lytton where there are commercial driveways. Between the initial project planning counts in May 1999 and the “before trial” counts in February 2003 are numerous long-term trends affecting traffic flows. In this case, the most important are the substantial downturn in the economy and (possibly) new development projects in the area. All these numerous factors can produce anomalies and inconsistencies in the data that are difficult to avoid. Staff always emphasizes that the comparisons of before-after counts must be considered approximate, with an error range of at least ­ + 10 percent.   One can be more confident that large changes in volumes, such as + 30 percent or greater, indicate “real” changes caused by the physical changes that one is trying to evaluate (such as the traffic calming measures). Nevertheless, the actual change could be at least 10 percent larger or smaller due to all the factors mentioned above.

1999 versus 2003 data. The first set of Downtown North counts was made in May 1999 at the start of the study. These counts were presented in Figure 4 of the Dowling Associates Final Technical Memorandum, Data Collection and Analysis, October 8, 1999, and included in Attachment B of this staff report. Staff has been using the 24-hour “perimeter cordon count” as the basis for comparing the effectiveness of various plans. This is the sum of the daily volumes at all the streets in/out of the neighborhood along Middlefield, Lytton and Alma. The total cordon count in May 1999 was approximately 28,000 vpd (using substitute counts for two minor streets not measured). Extensive traffic counts were taken again in February 2003 in preparation for implementing the trial, including numerous interior counts not taken in 1999 (see Attachment B). The cordon count total in February 2003 was approximately 24,000 vpd, a decrease of about 15 percent from the May 1999 planning counts. The decrease in traffic flows in and out of the neighborhood in those four years is most likely due to the economic downtown mentioned above, and specifically a combination of (i) reduced tripmaking by Downtown North residents due to a higher residential vacancy rate in the neighborhood and (ii) reduced through trips associated with Downtown Palo Alto, Stanford, and other mid-Peninsula areas.

In mid-1999, peak hour through traffic on Everett and Hawthorne was measured at 62 percent. It was on that basis that street closures were proposed and justified. By early 2000, the local economy was at its peak and traffic levels were higher than 1999. but by February 2003, when the pre-trial counts were measured, the economic bottom had already been reached, and a slight upturn was beginning. Local economic activity and, with it, traffic levels were low compared to 1999. The 15 percent cordon count reduction between 1999 and 2003 represented reduced the peak through traffic percentage to less than 60 percent, which is staff's minimum threshold to justify use of street closures for traffic calming. Thus, the downturn in economic activity eliminated some of the through traffic that the trial plan was designed to reduce. Staff believes that the prior conditions which formed the basis of the 1999 study will return and probably be exceeded, thus returning through traffic levels to at least the prior level that justified this project. This can be seen in the past history of volume counts on major arterials in Palo Alto over the past 30 years—a count in a given year or years can be lower than the preceding counts, but the long term trend has been an increase of about 1-2 percent annually.

“After” trial data. By September 2003, when the traffic counts were again measured after the trial plan had been in place for about four months, the cordon count had decreased substantially to about 13,700 vpd, a decrease of 43 percent from the February 2003 “before” cordon count (refer to map in Attachment B). The same daily and seasonal variations affected these counts also, but the longer-term issues are much less for a period of only six months. Perhaps the biggest changes in that six-month period were the opening of IKEA and the gradual upturn in the economy. There are substantial differences in individual counts between 1999 and 2003, as can be seen by comparing the counts for those years in Attachment B. A few examples stand out, such as Emerson between Lytton and Everett (4138 in 5/99 and 2085 in 2/03) and Webster between Lytton and Everett (865 in 5/99 and 1508 in 2/03). Staff does not have explanations for these individual anomalies other than some combination of the factors explained above. Fortunately, when performing a summation of many counts, such as the cordon count, the individual anomalies tend to become small compared to the total.

3.          Where did the diverted vehicles go?

As noted in the evaluation of the current trial plan (Attachment A of 1/21/04 PTC report), approximately 5000 through trips were removed from the neighborhood. Staff took extensive counts in the neighborhood and on the bordering arterials (Alma, Middlefield, Lytton), but only a few beyond that immediate area (five locations in the Lytton neighborhood and three in the Linfield Oaks area of Menlo Park). Staff and Dowling Associates had projected that the majority of the diverted trips from the traffic calming project would logically use the bordering arterials, which were the desirable routes for through trips. These increases were projected to be about 15 percent of existing volumes (or about 2500 vpd). In reality, the September 2003 “after” volume measurements at the four arterial count locations (D4, D10, D21, D26), showed no change at two locations. There was one notable increase (+23 percent on Lytton east of Cowper), and one notable decrease (-28 percent on Alma between Lytton and Everett). Three of these counts defy the logical predictions that there would be measurable increases on the bordering arterials.


The wider-area counts in the Lytton neighborhood east of Middlefield and the Linfield Oaks are in Menlo Park showed no measurable volume increases. Based on these counts and on feedback received from residents, staff believes that volumes have increased by varying amounts on parts (if not all) of Lytton between Middlefield and Alma, due to the traffic calming trial. But indications are that volumes have not increased as expected on Alma and Middlefield.

The street network is a wide “open network”, where drivers can choose any substitute route they want, based on the factors most important to them (travel time is typically the most important). The number of diverted trips caused by the traffic calming trial (about 5000) can therefore disperse to a large number of major and minor routes near and far from the neighborhood. In the portion of the network just a few blocks beyond the neighborhood, the 5000 diverted trips can easily disperse to many streets, and be less than the + 10 percent random daily fluctuation of the existing volume level--especially on the busy downtown area streets. Thus, it is not feasible to measure diversion beyond the first few blocks because the relatively small dispersed increases would be easily lost in the larger, varying volumes of most of these streets. If the origin and destination of each trip were known, it would be possible to roughly estimate what routes these drivers would choose. But it is not logistically or financially feasible to gather such data, and even with the data, the estimation of routes is fraught with inaccuracies. Drivers who used to cut through Downtown North streets who had non-local origins or destinations (e.g. live in San Mateo and work in the Stanford Research Park) could actually “disappear” from the nearby network by moving to a distant corridor, such as Ravenswood, Embarcadero, or Oregon Expressway. Staff suspects that El Camino Real and even Highway 101 might be serving as substitutes for some north-south trips that do not seem to have moved to Alma and Middlefield.

Clearly, it would be good to know exactly the impacts of traffic diversion projects in the wider context, but it is not practical. It is not even practical to measure small increments of change even on nearby roadways if they are major carriers (e.g., University Avenue). Staff focuses on measuring volume changes on the most vulnerable streets—the low volume local streets that are the most likely substitute routes within a few blocks of the project area.

4.          Comment on Unblock's report on issues related to the California Vehicle Code (CVC) and the California Environmental Quality Act (CEQA).

Some information is provided in this staff report in the section “Further Information on Policy Issues Raised in Public Testimony.”

5.          How do levels of through traffic in Downtown North (before the trial) compare to University South or other neighborhoods?

Through traffic on Everett in Downtown North was measured at approximately 62 percent during the AM peak in 1999. The average for the entire neighborhood for all streets (i.e., including even the low-volume streets off the main cut-through routes) was estimated to be about 45-50 percent. Through traffic on a particular route can only be determined accurately by a license plate matching study or an origin-destination questionnaire, both of which require extensive staff resources, so such studies have only been done for a few problem areas. Staff does not have through traffic data for the south of downtown area. Following are measured cut-through levels for some past traffic calming studies. Percentages represent the level of cut-through trips compared to total trips during the peak weekday hours on major internal cut-through routes (not neighborhood averages).

            Lytton neighborhood (1993, before traffic calming): 65-70%

            Evergreen Park neighborhood (1981, before street closures): 45%

            Churchill between Alma and Embarcadero (2001, no traffic calming): 40%

            College Terrace (1973, before street closures): 80%

            College Terrace (2002, with street closures): 65-70% (limited routes)

6.          Comment on the pedestrian benefits of bulbouts and if we can consider installing bulbouts at all four corners of Johnson Park.

The best bulbout design extends the curb line further into the street on one or both intersecting curblines of a corner. This enlarges the corner pedestrian area further out into the street and gives more area for pedestrians on the corner, as well as shortening the pedestrian street crossing. Bulbouts slightly narrow the driving area, but do not cause drivers to change course (such as for a traffic circle or chicane). Thus, they do not noticeably reduce speeds except for certain turning movements. The best nearby examples are on many of the corners of University Avenue and intersecting business district streets. The University Avenue bulbout corner radii are large to accommodate trucks and this limits how far into the street they can protrude. In Dowtown North next to the park, the radii could be smaller, so the bulbouts could extend into the streets about as far as a parked car. This would shorten crossing a 36-foot wide street to about 22 feet. The bulbout area is at sidewalk grade and thus provides protection for pedestrian waiting on the corner. The bulbout can be attractively paved or landscaped. This design requires a new drainage system for each bulbout, which is a high cost item. The paving and other surface amenities are also expensive. This design is relatively maintenance-free compared to the simple design described in the next paragraph. This design costs about $40,000 per pair. The four intersections bordering the park would require at least two pairs of bulbouts each, for a total of eight pairs, or about $300,000.

The set of bulbouts that was installed on Waverley next to Johnson Park for the Downtown North project is a simple, inexpensive design that provides only limited pedestrian protection by “shadowing” traffic flow in one direction. This design provides the same limited traffic calming as the expensive design because it narrows the street by the same amount. It lacks almost all of the aesthetic improvement that the full design would provide. It has relatively high maintenance costs, primarily due to the need for manual street sweeping and gutter clearing. This design was selected because it is far less expensive than the full design described above, at only about $5,000 per pair.   The total cost of installing two pairs of these bulbouts at each corner of the park (8 pairs) would be about $40,000. Bulbouts (of any design) replace at least one on-street parking place on each corner (unless parking is already prohibited for other reasons). This will improve corner visibility for both drivers and pedestrians.

The primary purpose of the Downtown North project is to reduce cut-through volume and, to a lesser extent, reduce speeds. As noted above, bulbouts provide only minimal benefit in these areas, especially in volume reduction, so staff does not believe that they should be installed as basic elements of the traffic calming plan, even around the park.

Question from Commissioner Holman:

1 .          How can the volume increases caused by the current trial plan on both sides of Johnson Park be improved (i.e, Kipling and Waverley)?  

One of the main reasons staff is recommending the Mixed Measures Plan is to specifically address that problem. The park, with its more concentrated pedestrian activity, is an area where volume increases are especially sensitive. The current trial plan provides only one north-south route (Kipling) between the closure on Hawthorne at Cowper and the one on Everett at Waverley; and two north-south streets (Waverley and Bryant) between the closure on Everett at Waverley and the one on Hawthorne at Bryant. The street closure locations in the Mixed Measure plan have been modified to open up the north-south routes in the central area of the neighborhood around the park. With the Mixed Measures Plan, there would be three north-south streets (Kipling, Waverley and Bryant) between the closure on Hawthorne at Cowper (unchanged location) and a relocated closure on Everett at Bryant. The turn restrictions in the Mixed Measures Plan are expected to offset some increase of cut through traffic due to the more open streets with this plan. Staff expects that these changes will keep any volume increases on the north-south streets near the park to an acceptable level (i.e., no greater than 25 percent increase over the “before” volumes measured in February 2003). The No Closures Plan should totally remove this problem of increased volumes on the north-south streets (but at the expense of less through-traffic reduction on other streets).

Questions from Commissioner Packer:

1.          Explain how each plan affects the problem of diverted volumes within the neighborhood.

Most of the unacceptable diverted traffic problems occurred on the north-south streets (one major exception was Ruthven). Staff identified four alternative plans in addition to fully removing the current trial plan. If “Remove Trial Plan” were implemented, there would be no diverted traffic within the neighborhood, although traffic levels would substantially rise on many street segments, especially along Hawthorne, Everett and Palo Alto Avenue, which would presumably return to the February 2003 “before trial” volumes. The “No Closures Plan” does not include any full time diversionary measures. The weekday turn restrictions would divert traffic around the neighborhood during the peak hours, with some of this re-entering the neighborhood via the north-south streets along Lytton. On a 24-hour weekday basis, these diverted volumes should be small enough to not cause unacceptable increases of traffic on any streets. The “Mixed Measures Plan” was discussed in the answer to the prior question from Commissioner Holman. The larger number of open north-south streets in the center of the neighborhood, counteracted by the peak hour turn restrictions, should reduce the increases measured on Cowper and Ruthven. In addition to expected reduction in diversion near the park, the removal of the closure on Everett next to Stanford Electric and the closure on Hawthorne at Bryant would open up the street network in that area and should therefore decrease the volume on Emerson. “Reduce Current Plan” opens up an additional north-south street (Waverley) between the closure on Hawthorne at Cowper and the closure on Everett at Waverley, as opposed to only one (Kipling) with the current plan. Removal of the closure near Stanford Electric should decrease the concentration of traffic on Emerson. Increases on Ruthven are not directly addressed by this plan. “Augment Current Plan” is based on the premise that much of the internal volume increases are caused by through traffic still passing through the neighborhood and making several jogs on the north-south streets to travel between Middlefield and Alma. The peak hour turn restrictions would further “tighten up” the neighborhood by adding even more out-of-path travel for through traffic. The hope is that these through trips would stay out of the center of the neighborhood, resulting in decreases in internal diverted traffic.

2.          What are the possibilities to alleviate the condition by Stanford Electric?

Except for “Augment Current Plan”, all the alternatives call for removal of the closure on Everett between High and Emerson, next to Stanford Electric, for two reasons. One is to make access into the neighborhood easier for Fire Department vehicles exiting Station One on Alma at Everett. Second, is to open up the first three blocks of Everett east of Alma to increase the traffic volume passing by Stanford Electric. This still does not give Stanford Electric access to the prior full-volume flow from which the business derives some “pass-by”customers, but at least there will be some flow. Note that, even with the current trial plan, Stanford Electric has unimpeded access from two major arterials: Alma and Lytton. The recommended Mixed Measures Plan, even though removing the Everett closure by Stanford Electric, will block direct access from southbound Alma during six peak hours on weekdays. The current closure design employs a concrete block and flexible post which can be traversed (in the eastbound direction) by fire trucks. Stanford Electric trucks can also traverse this closure (not legally) if they need to use Emerson to exit the area. Neither the current block/flexible post closure design, nor any other “permeable” design, is intended to help Stanford Electric customers. These designs are only meant for emergency vehicles and possibly PASCO truck